964 resultados para Differential response


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There are emerging movements in several countries to improve policy and practice to protect children from exposure to domestic violence. These movements have resulted in the collection of new data on EDV and the design and implementation of new child welfare policies and practices. To assist with the development of child welfare practice, this article summarizes current knowledge on the prevalence of EDV, and on child welfare services policies and practices that may hold promise for reducing the frequency and impact of EDV on children. We focus on Australia, Canada, and the United States, as these countries share a similar socio-legal context, a long history of enacting and expanding legislation about reporting of maltreatment, debates regarding the application of reporting laws to EDV, and new child welfare practices that show promise for responding more effectively to EDV.

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In this Issues Paper, I raise some key points relevant for any government which is considering its child protection and family welfare policy. In particular, I will raise questions about whether a form of legislative reporting duty is required, and if so, what consequences this has for child protection. The context of child maltreatment - and each form of maltreatment: physical abuse, sexual abuse, psychological or emotional abuse, and neglect - is extremely complex, and the overarching question of how to deal with these phenomena involve challenging normative, economic and practical questions. There are no easy or perfect solutions. Nor, often, is there the amount and quality of evidence available on which public policy approaches should be devised. However, from the best evidence about the history of this context, from research conducted in this field, and from the best evidence available about the nature, incidence and effects of different subtypes of maltreatment, some observations can be made which may help to inform deliberations. I outline 10 key issues related to mandatory reporting legislation while being mindful of the New Zealand context. My view, based on both research evidence and a concern to protect and promote children’s interests, and society’s interests, is that reporting laws in some form are necessary and can contribute substantially to child protection and enhancing family and community health and wellbeing. However, they are only one necessary part of a sound child protection system, being a method of tertiary and secondary prevention, and primary prevention efforts must also be prioritised. Moreover, it is essential that if a legislative reporting duty is enacted, it must be designed carefully and implemented soundly, and it must be integrated within a properly resourced child protection and family welfare system.

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This chapter describes the features of different Australian State and Territory laws and policies about child neglect. It makes observations about three major domains of law and policy: laws about child neglect to enable protection of children who are suffering severe neglect (child protection laws); laws and policies about the provision of services for children and their families when experiencing neglect (support-oriented laws and policies); and criminal laws about child neglect.

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Nurr1, NGFI-B and Nor1 (NR4A2, NR4A1 and NR4A3, respectively) belong to the NR4A subfamily of nuclear receptors. The NR4A receptors are orphan nuclear receptors which means that activating or repressing ligands for these receptors have not been found. NR4A expression is rapidly induced in response to various stimuli including growth factors and the parathyroid hormone (PTH). The studies concerning the NR4A receptors in the central nervous system have demonstrated that they have a major role in the development and function of the dopaminergic neurons of the midbrain and in regulating hypothalamus-pituitary-adrenal-axis. However, the peripheral functions of the NR4A family are largely unknown. Cultured mouse primary osteoblasts, a preosteoblastic cell line and several osteoblastic cell lines were used to investigate the role of NR4A receptors in osteoblasts. NR4A receptors were shown to directly bind to and activate the promoter of the osteopontin gene (OPN) in osteoblastic cells, thus regulating its expression. OPN is a major bone matrix protein expressed throughout the differentiation of preosteoblastic cells into osteoblasts. The activation of the OPN promoter was shown to be dependent on the activation function-1 located in the N-terminal part of Nurr1 and to occur in both monomeric and RXR heterodimeric forms of NR4A receptors. Furthermore, PTH was shown to upregulate OPN expression through the NR4A family. It was also demonstrated that the fibroblast growth factor-8b (FGF-8b) induces the expression of NR4A receptors in osteoblasts as immediate early genes. This induction involved phosphatidylinositol-3 kinase, protein kinase C, and mitogen activated protein kinase, which are all major pathways of FGF signalling. Nurr1 and NGFI-B were shown to induce the proliferation of preosteoblastic cells and to reduce their apoptosis. FGF-8b was shown to stimulate the proliferation of osteoblastic cells through the NR4A receptors. These results suggest that NR4A receptors have a role both in the differentiation of osteoblasts and in the proliferation and apoptosis of preosteoblast. The NR4A receptors were found to bind to the same response element on OPN as the members of the NR3B family of orphan receptors do. Mutual repression was observed between the NR4A receptors and the NR3B receptors. This repression was shown to be dependent on the DNA-binding domains of both receptor families, but to result neither from the competition of DNA binding nor from the competition for coactivators. As the repression was dependent on the relative expression levels of the NR4As and NR3Bs, it seems likely that the ratio of the receptors mediates their activity on their response elements. Rapid induction of the NR4As in response to various stimuli and differential expression of the NR3Bs can effectively control the gene activation by the NR4A receptors. NR4A receptors can bind DNA as monomers, and Nurr1 and NGFI-B can form permissive heterodimers with the retinoid X receptor (RXR). Permissive heterodimers can be activated with RXR agonists, unlike non-permissive heterodimers, which are formed by RXR and retinoic acid receptor or thyroid hormone receptor (RAR and TR, respectively). Non-permissive heterodimers can only be activated by the agonists of the heterodimerizing partner. The mechanisms behind differential response to RXR agonists have remained unresolved. As there are no activating or repressing ligands for the NR4A receptors, it would be important to find out, how they are regulated. Permissiviness of Nurr1/RXR heterodimers was linked to the N-terminal part of Nurr1 ligand-binding domain. This region has previously been shown to mediate the interaction between NRs and corepressors. Non-permissive RAR and TR, permissive Nurr1 and NGFI-B, and RXR were overexpressed with corepressors silencing mediator for retinoic acid and thyroid hormone receptors (SMRT), and with nuclear receptor corepressor in several cell lines. Nurr1 and NGFI-B were found to be repressed by SMRT. The interaction of RXR heterodimers with corepressors was weak in permissive heterodimers and much stronger in non-permissive heterodimers. Non-permissive heterodimers also released corepressors only in response to the agonist of the heterodimeric partner of RXR. In the permissive Nurr1/RXR heterodimer, however, SMRT was released following the treatment with RXR agonists. Corepressor release in response to ligands was found to differentiate permissive heterodimers from non-permissive ones. Corepressors were thus connected to the regulation of NR4A functions. In summary, the studies presented here linked the NR4A family of orphan nuclear receptors to the regulation of osteoblasts. Nurr1 and NGFI-B were found to control the proliferation and apoptosis of preosteoblasts. The studies also demonstrated that cross-talk with the NR3B receptors controls the activity of these orphan receptors. The results clarified the mechanism of permissiviness of RXR-heterodimers. New information was obtained on the regulation and functions of NR4A receptors, for which the ligands are unknown.

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Ant-plant interactions often are mediated by extrafloral nectar (EFN) composition that may influence plant visitation by ants. Over a 300 km range in the Indian Western Ghats, we investigated the correlation between the EFN composition of the myrmecophytic ant-plant Humboldtia brunonis (Fabaceae) and the number and species of ants visiting EFN. EFN composition varied among H. brunonis populations and between plant organs (floral bud vs. young leaf EFN). In general, EFN was rich in sugars with small quantities of amino acids, especially essential amino acids, and had moderate invertase activity. In experiments at the study sites with sugar and amino acid solutions and with leaf or floral bud EFN mimics, dominant EFN-feeding ants differentiated between solutions as well as between mimics. The castration parasite Crematogaster dohrni (northern study site) was the least selective and did not exhibit any clear feeding preferences, while the largely trophobiont-tending non-protective Myrmicaria brunnea (middle study site) preferred higher sucrose concentrations and certain essential/non-essential amino acid mixtures. The mutualistic Technomyrmex albipes (southern study site) preferred sucrose over glucose or fructose solutions and consumed the leaf EFN mimic to a greater extent than the floral bud EFN mimic. This young leaf EFN mimic had low sugar concentrations, the lowest viscosity and sugar: amino acid ratio, was rich in essential amino acids, and appeared ideally suited to the digestive physiology of T. albipes. This preference for young leaf EFN may explain the greater protection afforded to young leaves than to floral buds by T. albipes, and may also help to resolve ant-pollinator conflicts. The differential response of dominant ants to sugar, amino acids, or solution viscosity suggests that plants can fine-tune their interactions with local ants via EFN composition. Thus, EFN can mediate local partner-choice mechanisms in ant-plant interactions.

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Cancer is a complex disease which arises due to a series of genetic changes related to cell division and growth control. Cancer remains the second leading cause of death in humans next to heart diseases. As a testimony to our progress in understanding the biology of cancer and developments in cancer diagnosis and treatment methods, the overall median survival time of all cancers has increased six fold one year to six years during the last four decades. However, while the median survival time has increased dramatically for some cancers like breast and colon, there has been only little change for other cancers like pancreas and brain. Further, not all patients having a single type of tumour respond to the standard treatment. The differential response is due to genetic heterogeneity which exists not only between tumours, which is called intertumour heterogeneity, but also within individual tumours, which is called intratumoural heterogeneity. Thus it becomes essential to personalize the cancer treatment based on a specific genetic change in a given tumour. It is also possible to stratify cancer patients into low- and high-risk groups based on expression changes or alterations in a group of genes gene signatures and choose a more suitable mode of therapy. It is now possible that each tumour can be analysed using various high-throughput methods like gene expression profiling and next-generation sequencing to identify its unique fingerprint based on which a personalized or tailor-made therapy can be developed. Here, we review the important progress made in the recent years towards personalizing cancer treatment with the use of gene signatures.

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We report the implementation of a micro-patterned, glass-based photonic sensing element that is capable of label-free biosensing. The diffractive optical analyzer is based on the differential response of diffracted orders to bulk as well as surface refractive index changes. The differential read-out suppresses signal drifts and enables time-resolved determination of refractive index changes in the sample cell. A remarkable feature of this device is that under appropriate conditions, the measurement sensitivity of the sensor can be enhanced by more than two orders of magnitude due to interference between multiply reflected diffracted orders. A noise-equivalent limit of detection (LoD) of 6 x 10(-7) was achieved with this technique with scope for further improvement.

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Position-dependent gene expression is a critical aspect of the development and behaviour of multicellular organisms. It requires a complex series of interactions to occur between different cell types in addition to intracellular signalling cascades. We used Escherichia coli to study the properties of an artificial signalling system at the interface between two expanding cell populations. We genetically engineered one population to produce a diffusible acyl-homoserine lactone (AHL) signal, and another population to respond to it. Our experiments demonstrate how such a signal can be used to reproducibly generate simple visible patterns with high accuracy in swimming agar. The producing and responding cassettes of two such signalling systems can be linked to produce a symmetric interface for bidirectional communication that can be used to visualise molecular logic. Intracellular feedback between these two cassettes would then create a framework for self-organised patterning of higher complexity. Adapting the experiments of Basu et al. (Basu et al., 2005) using cell motility, rather than a differential response to AHL concentrations as a way to define zones of response, we noted how the interaction of sender and receiver cell populations on a swimming plate could lead to complex pattern formation. Equipping highly motile strains such as E. coli MC1000 with AHL-mediated auto-inducing systems based on Vibrio fischeri luxI/luxR and Pseudomonas aeruginosa lasI/lasR cassettes would allow the amplification of a response to an AHL signal and its propagation. We designed and synthesised codon-optimised auto-inducing luxI/R and lasI/R cassettes as optimal gene expression is crucial for the generation of robust patterns. We still have to complete and test the entire genetic circuitry, although by modelling the system we were able to demonstrate its feasibility. © 2007 The Institution of Engineering and Technology.

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地处干旱半干旱区的我国北方温带草原是欧亚大陆草原生物区系的重要组成部分,对全球变化敏感。土壤微生物在联系生态系统地上和地下部分起着中枢作用,由于其周转速率快,对环境因子变化响应快速,可用来指示短期内环境因子的变化对生态系统的影响。目前关于内蒙古半干旱温带草原的研究主要集中在生态系统地上部分,对地下尤其是土壤微生物对全球变化及人为干扰的响应研究仍然缺乏。本研究选取位于内蒙古多伦县的代表性的半干旱温带草原,通过对多种环境因子变化及人为干扰下土壤微生物量、呼吸、氮可利用性及转化等参数进行测定,旨在探讨全球变化及人为干扰对土壤微生物的影响,为地上植物群落的响应及生态系统地上与地下部分的联系提供机理解释,研究结果如下: 通过研究土壤微生物生物量和呼吸生长季的动态变化,以及它们对地形、火烧、施用氮肥及其交互作用的响应,结果表明,土壤微生物参数在生长季表现出明显的季节变异。土壤微生物生物量碳(MBC)、氮(MBN)分别在坡下比坡上高出14.8%和11.5%。但是,有机碳微中生物量碳的百分比(Cmic/Corg)以及总氮中微生物量氮的百分比(Nmic/Ntot)分别在坡上比坡下高16.9%和26.2%。微生物呼吸(MR)和代谢熵(qCO2)都不受地形的影响。火烧在整个生长季分别提高MBC和MBN29.8%和14.2%,MR和qCO2 则有降低趋势,尤其是在八月份。火烧在坡上提高Cmic/Corg 和Nmic/Ntot,但是在坡下对二者没有影响。氮肥的施用在第一个生长季对所有土壤微生物指标都没有影响。 草原生态中环境因子的空间和时间变异可以影响土壤微生物以及它们对干扰的响应。通过对地形、火烧、施肥进行三年连续处理和观测土壤微生物指标发现,1)土壤微生物参数有明显的年际变异。2)在相对湿润的年份,土壤微生物量在坡下比坡上高,但是Cmic/Corg和Nmic/Ntot 在坡上高于坡下。但在干旱年份里,所有土壤微生物参数都是在坡下高于坡上,且由于地形引起的差异在干旱年份表现更强烈。MBC、MBN、MR 的变异系数在坡上高,表明土壤微生物量和活性在坡下稳定性高。说明了土壤水分含量在半干旱温带草原调节土壤微生物和其稳定性方面起着重要作用。地形对土壤可利用的氮没有影响。3)每年一次的火烧对土壤微生物量、Cmic/Corg、Nmic/Ntot 有正效应但正效应随处理时间延长和处理次数增加而降低。火烧在在第一年内不论在坡上还是坡下都降低MR,但是在干旱年份里,火烧在坡上降低MR,在坡下提高MR。火烧在第二年里在坡下提高了土壤无机氮含量,但在坡上降低了土壤无机氮含量。在第三年,不论坡上还是坡下,火烧使得土壤无机氮含量降低。4)施用氮肥提高土壤无机氮含量,但是它对土壤微生物参数产生负效应,且负效应随着处理时间延长和处理次数的增加而增强。此外,氮肥增加了MBC、MBN、MR的变异系数。 土壤微生物在生态系统碳氮循环中起着关键作用,但是关于氮素添加是否促进或抑制土壤微生物生物量和活动仍然存在争议。在我国北方温带草原的这项研究目的在于探讨土壤微生物沿着一个施氮梯度的响应。本研究设置了每年一次、连续四年的八个水平(0, 1, 2, 4, 8, 16, 32, 64 g N m-2以尿素形式施入土壤)N处理。并在第三年和第四年测定了土壤微生物生物量碳、氮、磷、微生物呼吸和代谢熵、土壤无机氮、净氮矿化和硝化。大多数测定的微生物参数都在低施氮处理下有所增加,相反在高施氮处理下降低。在取样测定的两年中,对土壤微生物生长和活动的最适施氮量大致为2 g N m-2 y-1;而施氮的阈值在16 和32 gN m-2 y-1之间,在此阈值之上,土壤pH、微生物生物量、微生物呼吸、Cmic/Corg、Nmic/Ntot 急剧降低,相反,土壤无机氮、净氮矿化和硝化急剧增加。土壤微生物对低施氮处理和高施氮处理的特异性响应(Differential Response)可能是由于微生物碳氮限制的转换、以及高施氮处理下土壤pH值降低的毒害影响而引起的。本研究中观察到的土壤微生物沿着施氮梯度的非线性响应有助于解决不同报道及不同生态系统中氮素添加对土壤微生物影响的争议。 气候变化将显著影响陆地生态系统的碳循环。以2005年4月开始的一项野外控制实验为平台,检验我国北方半干旱典型草原土壤和微生物呼吸以及微生物生物量对试验增温和增加降水的响应。在3 个实验年份内(2005-2007 年)测定了整个生长季节的土壤呼吸、微生物呼吸、微生物生物量碳和微生物生物量氮。结果表明,1)受到降水年际波动的影响,土壤和微生物呼吸以及微生物生物量均存在明显的年际变化。2)实验室内沿着一个水分梯度的培养实验揭示了微生物呼吸对温度的响应受到低土壤水分含量的限制。3)在三年时间内,试验增温引起土壤和微生物呼吸以及微生物生物量的显著降低,说明试验增温通过加剧土壤水分胁迫的间接负效应大于温度增加的直接正效应。试验增温所引起的蒸发散的增加导致土壤水分可利用性减少到某一胁迫阈值(Threshold)之下,并因此抑制了植物生长、根系和微生物活动。4)降水增加显著刺激了土壤和微生物呼吸以及其它微生物参数,而且这种正效应随着时间而增强。研究结果表明:在半干旱温带草原,土壤水分在调节土壤和微生物呼吸以及微生物生物量及其对气候变化的响应方面所起的作用比温度更为重要。比较温带草原土壤呼吸与总初级生产力的相对变化显示,相对于光合碳固定而言,增温导致更多而增雨引起较少的呼吸碳损失。这一发现说明:除非降水增加,气候变暖情形下,我国北方的干旱半干旱温带草原将可能作为一个净的碳源。

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The effect of increasing concentrations (65, 130, 325, 1,300, and 3,250 μg/g soil dry weight) of 1,2-dichlorobenzene (1,2-DCB) on the microbial biomass, metabolic potential, and diversity of culturable bacteria was investigated using soil microcosms. All doses caused a significant (p < 0.05) decrease in viable hyphal fungal length. Bacteria were more tolerant, only direct total counts in soils exposed to 3,250 μg/g were significantly (p < 0.05) lower than untreated controls, and estimates of culturable bacteria showed no response. Pseudomonads counts were stimulated by 1,2-DCB concentrations of up to 325 μg/g; above this level counts were similar to controls. Fatty acid methyl ester analysis of taxonomic bacterial composition reflected the differential response of specific genera to increasing 1,2-DCB concentrations, especially the tolerance of Bacillus to the highest concentrations. The shifts in community composition were reflected in estimates of metabolic potential assessed by carbon assimilation (Biolog) ability. Significantly fewer (p < 0.05) carbon sources were utilized by communities exposed to 1,2-DCB concentrations greater than 130 μg/g (<64 carbon sources utilized) than control soils (83); the ability to assimilate individual carbohydrates sources was especially compromised. The results of this study demonstrate that community diversity and metabolic potential can be used as effective bioindicators of pollution stress and concentration effects.

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The cell cycle comprise the four phases of, G1, S-phase, G2 and mitosis. Two critical transitions are G1/S and G2/M; the latter is regulated by WEE1 kinase and CDC25 phosphatases. The scope of this thesis was to investigate the regulation of the G2/M transition of the cell cycle by WEE1 and CDC25, and how these genes interface with plant growth regulators in Arabidopsis thaliana. In Arabidopsis roots, the frequency of lateral roots was found to be increased by ectopic expression of Schizosaccharomyces pombe (Sp)cdc25e and reduced by Arath;WEE1 expression. I examined the effect of Arath;WEE1 and Spcdc25 on induction of shoots and roots in Arabidopsis hypocotyls in vitro. Hypocotyl explants from two over-expressing WEE1 lines , three T-DNA insertion lines and two expressing cdc25 (Spcdc25e) lines together with wild type (WT) were cultured on two-way gradients of kinetin (Kin) and naphthyl acetic acid (NAA). Below a threshold concentration of NAA (100 ng ml-1), WEE1 repressed morphogenesis in vitro, whereas at all NAA/Kin combinations Spcdc25 promoted morphogenesis (particularly root formation) over and above that in WT. Loss of function wee1-1 cultures were very similar to WT. Quantitative data indicated a significant increase in the frequency of root formation in Spcdc25e cultures compared with WT particularly at low Kin concentrations, and WEE1oe’s repressive effect was overcome by NAA but not Kin. In conclusion, WEE1 has a repressive effect on morphogenesis in vitro that can be overcome by auxin whereas Spcd25 by-passes a cytokinin requirement for the induction of morphogenesis in vitro. The role of CDC25 and WEE1 in DNA damage responses was also analysed. Two over-expressing Arath;CDC25 lines and T-DNA mutants showed no difference to WT either in standard conditions or zeocin-supplemented treatments. However, root length was longer in Arath;CDC25oe lines treated with hydroxyurea (HU) and lateral root number was increased compared to WT. This suggests a differential response of Arath;CDC25oe in the DNA replication (HU-induced) and DNA damage (zeocin-induced) checkpoints (Chapter 5). Finally the roles of WEE1 and CDC25 in cell cycle regulation were examined using tobacco TBY-2 cell cultures expressing Arath;WEE1, Nicotiana tabacum (Nicta)WEE1 or Arath;CDC25. Whilst Nicta;WEE1 lengthened G2 of the cell cycle, Arath;WEE1 had an unusual effect of shortening G2 phase and Arath;CDC25 had no observable effect (Chapter 6).

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Investigations into the evolutionary origins of human cognition has shown that individuals’ memory for others is influenced by the latter’s behaviour in social contracts. Such research is primarily based on hypothetical or more abstract forms of social contracts, whereas an application of this knowledge to everyday health behaviours can be of great value. To address this, the current study investigated whether participants who were asked to imagine themselves in a hypothetical hazardous health scenario showed differential response sensitivity (d’) and latency (RT) to faces of hospital staff tagged with contrasting hand hygiene before touching patients: clean hands, dirty hands, or unknown hand-washing behaviour (control). The test used a two alternative forced-choice (2AFC: “old/new”) face recognition paradigm. The findings showed that d’ to dirty and clean hands was similar, but higher than for controls. Moreover, d’ was not affected by the occupation of hospital staff (nurses vs porters). The absence of memory gains towards clean or dirty hands points to the need for new strategies to remind patients to observe (and remember) the hand hygiene of others when exposed to hazardous health environments.

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Le virus de l’hépatite C (VHC) est un problème mondial. La majorité des personnes infectées (70-85%) développent une infection chronique qui cause des complications hépatiques. Le seul régime thérapeutique approuvé pour le VHC est l'interféron alpha (IFN-α). Ce traitement a un taux de réussite de 50-80% selon le génotype de virus et le moment de l'initiation de la thérapie. Les facteurs régissant la réponse au traitement ne sont pas bien définis. Des études antérieures ont suggéré un rôle potentiel de la réponse immunitaire de l'hôte au succès de la thérapie, toutefois, ces résultats sont controversés. Nous avons émis l'hypothèse que la réponse immunitaire de l’hôte sera plus efficace chez les patients qui commencent la thérapie tôt pendant la phase aiguë de l'infection. En revanche, la réponse immunitaire sera épuisée lorsque le traitement est initié pendant la phase chronique. L'objectif principal de ce mémoire est d’étudier les facteurs immunologiques qui régissent la réponse à la thérapie, et de déterminer si la contribution de la réponse immunitaire de l'hôte peut être influencée par la période de l'infection. Nos résultats démontrent l'efficacité de la restauration de la réponse immunitaire spécifique au VHC lorsque la thérapie par l'interféron est initiée tôt. Ceci est démontré par le sauvetage des cellules T efficaces spécifiques au VHC efficace similaires à celles observées chez les individus qui ont résolu spontanément, suggérant ainsi qu'elles jouent un rôle actif dans la réponse au traitement. Toutefois, cette réponse n'a pas été restaurée chez les patients traités au cours de la phase chronique. Ces résultats ont des implications importantes dans la compréhension des mécanismes sous-jacents à la réponse aux traitements actuels et au développement des nouvelles thérapies.

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PROBLÉMATIQUE La violence collective, à travers les guerres civiles et autres conflits politiques violents, constitue un lourd fardeau pour la santé publique. Plus de la moitié des décès causés par l’ensemble des conflits dans le monde entier se trouvent en Afrique. L’une des conséquences est le déplacement massif des populations qui se réfugient vers l’extérieur du pays, mais aussi de plus en plus à l’intérieur des frontières nationales. Ceux qui ne traversent pas sont appelés déplacés internes. Leur état de santé est au moins aussi vulnérable que celui de réfugiés, mais est très peu documenté. De 1993 à 2005, le Burundi a plongé dans une crise politico-sociale sans précédent. En 2001, environ 10 % de la population vivaient dans des camps de déplacés. OBJECTIF Documenter l’état de santé des personnes déplacées par la guerre au Burundi et identifier ses déterminants. CADRE CONCEPTUEL Le cadre conceptuel est basé sur la modélisation de l’association entre les événements traumatiques, les facteurs de l’environnement post-traumatique et l’état de santé des déplacés internes burundais. MÉTHODE Une enquête transversale a été menée dans deux camps de déplacés au Burundi. Les données ont été obtenues de façon rétrospective sur l’exposition aux événements traumatiques et de manière transversale pour l’état de santé et les facteurs de l’environnement post-traumatique. Les participants ont été interrogés sur les événements traumatiques vécus personnellement ou par leurs proches selon une courte échelle élaborée à cet effet. De même, les facteurs de l’environnement post-traumatique ont été documentés. Pour la mesure de l’état de santé, un questionnaire comportant certains des 17 items du profil de santé de Duke a été utilisé. Deux traductions ont été réalisées et plusieurs items ont été adaptés. RÉSULTATS Les événements traumatiques vécus par les déplacés internes burundais sont négativement associés à l’état de santé physique, à l’état de santé sociale, à l’état de santé perçu et, positivement, avec l’incapacité. De même, plusieurs facteurs de l’environnement post-traumatique sont associés à l’état de santé. Par contre, certaines associations sont à interpréter selon leurs interactions avec les événements traumatiques. Celles-ci agissent parfois comme modificateurs d’effet, en amortissant ou en amplifiant le lien associatif initial entre certains événements traumatiques et l’état de santé des déplacés. CONCLUSION : Les résultats font ressortir un effet différentiel associé d’une part aux événements traumatiques vécus précédemment et d’autre part, en interaction avec ces derniers, à l’environnement post-traumatique. Notre thèse en arrive à la conclusion que les facteurs de l’environnement post-traumatique constituent des déterminants importants de l’état de santé des déplacés de guerre.